Possible or not

Is it possible to have period like bleeding but still be pregnant? I had a few positive tests and now I’m bleeding bleeding. My friend said her mom didn’t know she was pregnant till 5 months because she got what she thought was her period for those few months and didn’t think anything of it till she got a belly and was like somethings fishy here. The pregnancy for her only showed on ultrasound which is weird but it happened. So I’m just curious as to how often heavy bleeding happens in early pregnancy.